Rows Of Plates Research Articles

Seismic Stability Limit Analysis of Unsaturated Soil Slopes Reinforced by Frame Beam Anchor Plates

The frame beam anchor plate (FBAP) reinforced slope has been popularized and applied in some fill slope projects. Nevertheless, the existing design method ignores the influence of earthquake action and the suction effect of unsaturated soils. The stability of unsaturated soil slopes reinforced with FBAPs under an earthquake is analyzed based on the upper bound theorem of limit analysis and pseudo-dynamic method to solve the above problems. The influence of the suction effect on the effective weight and strength of unsaturated soils under one-dimensional steady seepage conditions was considered in the derivation of the energy balance equation. A simplified method based on the volume integral of the rotating body is used to calculate the external work rate. Two possible failure modes of anchorage structures are considered when solving internal energy dissipation. Results show that the influence of suction and seepage conditions on slope stability decreases with the increasing soil pore size distribution parameter n and saturated hydraulic conductivity ks. Also, the stability of the slopes is significantly improved with the increase of total rows of anchor plates. Likewise, the stability of slopes decreases with the increase in the horizontal seismic coefficient kh and amplification coefficient fa.

Experimental evaluation of the size and distribution of lateral pressure on the walls of the excavation support

The paper presents the results of a research experiment that aimed at verifying the size and distribution of earth pressure acting on the excavation support with reference to commonly used theoretical solutions. The tests were carried out on the object in its full scale. For this purpose, a 6 m deep excavation was made in the testing ground. It was secured with a support system i.e., a point chamber consisting of corner columns and a system of three rows of fin plates. The tests relied on various measurement techniques. The earth pressure was measured with sensors specially designed and manufactured for this research experiment. Simultaneously with earth pressure measurements, there were measured stresses in the support plates with the use of strain gauges and deflections using laser scanning and a calibrated measurement patch. The tests were conducted for three months, with different backfill load. The measured values of earth pressure increased in a manner similar to the values of hydrostatic thrust, reaching max. 30 kPa before making the excavation and 25 kPa after making the excavation and assembling the support. The results were consistent with the values determined in line with commonly used theoretical solutions. The stresses caused a 15 mm deflection in the plates. Backfill load significantly affected the value of thrust down to a depth of approx. 4 m but did not cause a further increase in the deflection in the plates.

Effect of splitter damper on airflow conduction for thermal management of a lithium-ion battery cooling system with plate and cylindrical batteries

BackgroundThis paper simulates a lithium-ion battery pack (BRK) with cylindrical and plate batteries in an air duct. The batteries are arranged in rows of cylinders and plates in the BRK. A splitter damper is used at the air inlet and outlet in the duct. MethodsThis study was performed in a laminar airflow by changing the length of the splitter damper from 0.2 to 0.5 m, for both oval and triangular shapes of the splitter damper. Effects of various splitter damper settings on the BRK temperature, output air temperature, and heat transfer coefficient have been investigated. The BRK is simulated using COMSOL 6.0 software. Significant findingsAccording to the study's findings, the BRK greatest and lowest mean temperatures were measured along the 0.4 and 0.2 m of the splitter damper's triangular form, respectively. The heat transfer coefficient for the oval shape of the splitter damper was higher than the triangular shape of the splitter damper at all lengths of the splitter damper. The highest heat transfer coefficient is recorded in the oval form of a splitter damper with a length of 0.5 m.

REGARDING THE ATTRIBUTION OF SOME ITEMS FROM THE LYTA MOHYLA

The «Melgunov hoard» — a burial or burial-commemorative complex, which has been found during the excavations of the Lyta Mohyla in 1763, contained several items, functional destination of which is ambiguous.
 In particular, the gold plate with a depiction of a monkey and three birds is considered by most researchers to be a headdress decoration. However, the characters reproduced on the Melgunov plate in terms of nomenclature and represented subjects are close to the images on precious tableware made by Middle Eastern masters at different times.
 Therefore, it is more likely that this plate was cut from a thin-walled gold cup and was used to decorate the scabbard of a bladed weapon — a dagger or a long knife. Possessing two items of bladed weapons was widespread among the Scythians and it is recorded both in burials and on depiction of stone statues.
 17 plates in the form of a predatory bird are most often classified as belt decorations. But the presence of a gorytos in a burial and the established tradition of decorating arrow cases with gold plates give grounds for attributing these plates precisely as decorations of the gorytos. It does not contradict the area covered with sheets of the gorytos area; a composition formed by several rows of plates is possible; the image of a predatory bird is used; fastening to the leather base with the help of wide loops.
 One more item of bladed weapons in precious scabbard and a ceremonial gorytos, decorated with gold plates, confirm the high — royal — status of the owner of the set of items from the Lyta Mohyla. The proposed attributions, which assume the possible presence of several items of bladed weapons and a gorytos covered with precious plates in the burial complex, find full correspondence among the stable traditions of the Scythian culture.

Characterization of the complete mitochondrial genome of the brazilian cownose ray Rhinoptera brasiliensis (Myliobatiformes, Rhinopteridae) in the western Atlantic and its phylogenetic implications.

The Brazilian cownose ray, Rhinoptera brasiliensis has undergone a global population reduction and is currently classified by IUCN as Vulnerable. This species is sometimes confused with Rhinoptera bonasus, the only external diagnostic characteristic to distinguish between both species is the number of rows of tooth plates. Both cownose rays overlap geographically from Rio de Janeiro to the western North Atlantic. This calls for a more comprehensive phylogenetic assessment using mitochondria DNA genomes to better understand the relationships and delimitation of these two species. The mitochondrial genome sequences of R. brasiliensis was obtained by next-generation sequencing. The length of the mitochondrial genome was 17,759bp containing 13 protein-coding genes (PCGs), two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a non-coding control region (D-loop). Each PCG was initiated by an authoritative ATG codon, except for COX1 initiated by a GTG codon. Most of the PCGs were terminated by a complete codon (TAA/TAG), while an incomplete termination codon (TA/T) was found in five out of the 13 PCGs. The phylogenetic analysis showed that R. brasiliensis was closely related to R. steindachneri whereas the reported mitogenome as R. steindachneri (GenBank accession number KM364982), differs from multiple mitocondrial DNA sequences of R. steindachneri and is nearly identical to that of R. javanica. The new mitogenome determined in this study provides new insight into the phylogenetic relationships in Rhinoptera, while providing new molecular data that can be applied to population genetic studies.

An experimental study of a rectangular floating breakwater with vertical plates as wave-dissipating components

Floating breakwaters have received growing attention in recent years from academic and engineering sectors alike. The wave-dissipating components are commonly attached to the bottom of floating breakwaters for better wave protection performance. Vertical plates, which have been proven effective in dissipating waves, were attached to a rectangular floating breakwater in this study. A series of experiments were conducted under regular wave conditions to analyze the wave protection and motion response performances, and the effects of mounting position, mounting rows, plate porosity, and protruding plate height were examined. Our experimental results elucidated that the pitch motion plays a critical role in dissipating energy. Although variation in the settings, such as mounting with more than one row of plates, smaller plate porosity and longer protruding plate height do not cause significant changes in the mass and moment of inertia of floating breakwater, they all exert stronger confining effects on the water body beneath. The water body confined by plates significantly changes the dynamic characteristics of floating breakwaters, and increase the natural period of pitch motion towards longer waves. As a result, the violent energy dissipation and corresponding better wave protection occur at longer waves. It has been demonstrated that the primary working function of vertical plates as wave-dissipating components is due to water body confinement. This finding can be utilized to tailor the design of the vertical plates as wave-dissipating components in accordance with the seasonal weather and sea conditions at specific engineering sites.

New species of Farlowella (Siluriformes: Loricariidae) from the rio Tapajós basin, Pará, Brazil

Abstract A new species of stick-catfish Farlowella is described from streams of the lower rio Tapajós drainage, in Pará State, northern Brazil. The new species is distinguished from all congeners by a naked gular region (vs. gular region with plates) and from most congeners by the presence of five lateral series of plate rows on anterior region of body (vs. four). The new species shows variation in the series of abdominal plates and a discussion on the variation of abdominal plates within Farlowella is made and comments on synapomorphic characters in Farlowellini.

The research on dynamic performance of single channel selective catalytic reduction system with different shapes

This work tried to improve the denitration (de-NOx) performance of the selective catalytic reduction (SCR) system by changing the structure of the channel, and identify the factors affecting SCR catalytic reaction. A single channel in the catalytic converter is selected as the research object and a three-dimensional internal flow model is established. Firstly, the simulation results are compared with the experimental results to verify the reliability of the model. Secondly, the flow, species transfer and catalytic reaction in a single channel with different cross-section shapes are simulated and compared comprehensively. The results show that changing shape of the channel can improve the de-NOx performance and decrease the pressure drop. At the inlet velocity of 20 m/s, the circular channel has the largest NOx conversion efficiency (66.2%) and is 0.61% higher than that of the square channel. The pressure drop of circular channel is the smallest, which is 50 Pa less than that of the square channel. Finally, using channel shape, inlet velocity and NO2/NOx as the optimal variables, the orthogonal experimental design has been made. The results show that the influence of inlet velocity on NOx conversion efficiency and pressure drop is the most significant. The combination of the highest NOx conversion efficiency is the inlet velocity of 10 m/s, corrugated plate row, and NO2/NOx ratio of 0.5. The research on the single channel flow and reaction can provide theoretical and engineering reference for the subsequent research on multi-channel flow and reaction characteristics in the real SCR system.

Description of Xenotrichula tropicalis sp. nov. (Gastrotricha: Chaetonotida) and New Records of Xenotrichulidae Species from Brazil and USA

Sampling of twelve locations along the north east coast of the USA and Brazilian coasts yielded five new records of Xenotrichulidae species (Xenotrichula guadalupensis, X. carolinensis, X. intermedia, Heteroxenotrichula pygmaea and Draculiciteria tesselata) and the description of a new species of Xenotrichula, X. tropicalis sp. nov. from Brazil. The new species is unique among its congeners in possessing double edge rounded scales on the ventral edge of the pharynx and two rows of flat plates on the ventral trunk.

Bipolar electrodeposition of spongy lead from alkaline solutions on a flow wire cathode

For alkali solution electrolysis resulting in the production of lead dioxide on anode and lead sponge on cathode, the concentration of lead on cathode should be high and that on anode should be low. To prevent sponge from coming off of the cathode leading to electrode bridging, low current densities should be used. In this case, the adhesion of sponge to cathode will be stronger. Another solution would be to use a dielectric mesh to separate the cathode and the anode. To improve the process conditions, it is proposed to use a porous lead sponge to separate catholyte from anolyte. The sponge can act as a flow cathode at the same time. A metallic mesh, a row of parallel rods or plates or other type of permeable cathode are proposed as the basis for growing the sponge. The proposed technique helps precipitate the lead sponge predominantly on the backside of the cathode preventing the cathode deposit from hitting the anode and thus preventing electrode bridging. As the cathode sponge goes all the way across the section of the cell, the pregnant solution concentrates in between the cathodes while the weak solution concentrates near the anodes. This leads to a higher depletion of the solution and helps lower the concentration of lead near the anodes and control the generation of lead oxides on anode. Compared with conventional techniques when the sideways growth of the spongy precipitate is constrained by the cross section of the cell (from 200–300 to 400–500 A/m2), this technique also helps significantly increase the current density at low power consumption and obtain a high-purity lead sponge. In comparison with high-intensity electrolysis techniques, the above described technique helps significantly decrease the power consumption, improve the purity of cathode deposits and lower the concentration of lead in the spent electrolyte. This process does not require higher temperatures, thus there is no need in alkaline vapour suppression equipment.

Surface Curvature Effects on Film Cooling Performance for Shaped Holes on a Model Turbine Blade

Abstract Surface curvature has been shown to have significant effects on the film cooling performance of round holes, but the literature include few studies of its effects on shaped holes despite their prevalence in gas turbines. Experiments were performed using two rows of holes placed on the suction side of a scaled-up turbine blade in a low Mach number linear cascade wind tunnel with low freestream turbulence. The rows were placed in regions of high and low convex surface curvature. Geometries and flow conditions for the rows were matched to those from previous flat plate studies. Comparison of the adiabatic effectiveness results from the high curvature and flat plate rows revealed the same trends as those in the literature using round holes, with increased performance for the high curvature row at lower blowing ratios and the opposite at higher ones. The low curvature row had similar performance to the flat plate row at lower blowing ratios, suggesting the mild convex curvature had little beneficial effect. At higher blowing ratios, the low curvature row had inferior performance, which was attributed to the local freestream adverse pressure gradient that generated additional turbulence, promoting jet-to-mainstream mixing and decreasing performance.

Are stable isotope ratios and oscillations consistent in all baleen plates along the filtering apparatus? Validation of an increasingly used methodology.

Baleen plates are anatomical structures composed of inert tissue that hang from the upper jaw in mysticetes. Baleen plates may differ in size and in coloration between different segments of the filtering row or between sides of the mouth. Concern has been raised that variation in baleen plate characteristics may reflect dissimilar structural composition and growth rates liable to affect stable isotope ratios and their oscillation patterns. We measured stable carbon (δ13 C values) and nitrogen (δ15 N values) isotope ratios at intervals of 1cm along the longitudinal axis of six baleen plates collected from different positions along the mouth of a fin whale. All samples were analysed using a continuous flow isotope ratio mass spectrometer. Generalized additive models were fitted to the data from each baleen plate and the results of the models were compared visually. A total of 206 samples were analysed. Visually, all baleen plates presented nearly identical oscillations, independent of the position or the coloration of the baleen plate. However, the variation in δ13 C and δ15 N values occurring between the different baleen plates was higher in the segments of oscillations exhibiting steeper slopes. Differences in size between plates in an individual are due to differential erosion rates according to their position in the mouth. Therefore, the position of sampling along the baleen plate row should not be a reason for concern when conducting stable isotope studies.

Hydraulic performance of abrupt outlet transition structure with strip guide vanes at subcritical flow

For some stream structures such as barrages, regulators, as well as change of channel cross section, the downstream expansion transitions structures are the common requirement. Eddies, as a result of the flow separation in such structures leads to destruction the bed and sides of the downstream channel. Head loss, on the other hand, produced through the expansion is important because it affects the stage at downstream. This study is restricted to developing the hydraulic performance of abrupt outlet transition at subcritical flow for both decreasing the head losses besides spreading the flow transversely to achieve regular velocity across the width as much as possible. New appurtenances, is adopting to install at specified configuration into a sudden transition. The appurtenances consisted of two successive rows of thin plates used as guide vanes to direct and spread the flow across the width with more uniformity. The guide vanes also keep the head losses at minimum possible. This attempt, through the results, proved that it has considerable hydraulic and economic advantages as compared to using a flared wall. Greater uniformity in velocity distributions of flow across the width, shorter length, and 70% lesser head loss are the results of the hydraulic performance of abrupt expansion transition equipped with two sets of strip vanes as compared to that with the plain one.

Anal sac of a cladid crinoid from Permo-Carboniferous Talchir Formation, Talchir basin, Odisha

A calcareous anal sac of a probable cladid crinoid, referable to Cyathocrinitacea family is reported for the first time from late Carboniferous-early Permian siliciclastics of Talchir basin, Angul district, Odisha. A cladid affinity for this crinoid specimen is confirmed from tubular, anteriorly tapered anal sac with slightly alternating, multiple rows of calcified plates, hexagonal or modified hexagonal, pentagonal and polygonal plate sutures with pitted plate surface. Generic identification is not attempted due to the incomplete preservation of the specimen. The preservation of this exclusive marine organism in the fine siliciclastics attests to a marine depositional milieu.

Ontogeny of the Electric Organs in the Electric Eel, Electrophorus electricus: Physiological, Histological, and Fine Structural Investigations

This study attempts to clarify the controversy regarding the ontogenetic origin of the main organ electrocytes in the electric eel, Electrophorus electricus. The dispute was between an earlier claimed origin from a skeletal muscle precursor [Fritsch, 1881], or from a distinct electrocyte-generating matrix, or germinative zone [Keynes, 1961]. We demonstrate electrocyte formation from a metamerically organized group of pre-electroblasts, splitting off the ventralmost tip of the embryonic trunk mesoderm at the moment of hatching from the egg. We show details of successive stages in the development of rows of electric plates, the electrocytes, by means of conventional histology and electron microscopy. The membrane-bound pre-electroblasts multiply rapidly and then undergo a specific mitosis where they lose their membranes and begin extensive cytoplasm production as electroblasts. Electrical activity, consisting of single and multiple pulses, was noticed in seven-day-old larvae that began to exhibit swimming movements. A separation of discharges into single pulses and trains of higher voltage pulses was seen first in 45-mm-long larvae. A lateralis imus muscle and anal fin ray muscles, implicated by earlier investigators in the formation of electrocytes, begin developing at a time in larval life when eight columns of electrocytes are already present. Axonal innervation is seen very early during electrocyte formation.

Studies on woloszynskioid dinoflagellates VI: description of Tovellia aveirensis sp. nov. (Dinophyceae), a new species of Tovelliaceae with spiny cysts

A new species of Tovellia, T. aveirensis, is described on the basis of light (LM) and scanning electron microscopy (SEM) of motile cells and resting cysts, complemented with transmission electron microscopy (TEM) of flagellate cells and phylogenetic analysis of partial sequences of the large subunit ribosomal rRNA gene. Both vegetative cells and several stages of a life cycle involving sexual reproduction and the production of resting cysts were examined in cultures established from a tank in the University of Aveiro campus. Vegetative cells were round and little compressed dorsoventrally; planozygotes were longer and had a proportionally larger epicone. Chloroplast lobes were shown by TEM to radiate from a central, branched pyrenoid, although this was difficult to ascertain in LM. The amphiesma of flagellate cells had mainly 5 or 6-sided vesicles with thin plates, arranged in 5–7 latitudinal series on the epicone, 3–5 on the hypocone. The cingulum had 2 rows of plates, the posterior row extending into the hypocone and crossed by a series of small projecting knobs along the lower edge of the cingulum. A line of narrow amphiesmal plates extended over the cell apex, from near the cingulum on the ventral side to the middle of the dorsal side of the epicone. Eight or 9 narrow amphiesmal plates lined each side of this apical line of plates (ALP). Resting cysts differed from any described before in having numerous long, tapering spines with branched tips distributed over most of the surface. Most mature cysts showed an equatorial constriction. Neither cysts nor motile cells were seen to accumulate red cytoplasmic bodies in any stage of the cultures. The phylogenetic analysis placed, with high statistical support, the new species within the genus Tovellia; it formed a clade, with moderate support, with T. sanguinea, a species notable for its reddening cells.

Cilia and the life of ctenophores

AbstractCtenophores, or comb jellies, are a distinct phylum of marine zooplankton with eight meridional rows of giant locomotory comb plates. Comb plates are the largest ciliary structures known, and provide unique experimental advantages for investigating the biology of cilia. Here, I review published and unpublished work on how ctenophores exploit both motile and sensory functions of cilia for much of their behavior. The long‐standing problem of ciliary coordination has been elucidated by experiments on a variety of ctenophores. The statocyst of ctenophores is an example of how mechanosensory properties of motile cilia orient animals to the direction of gravity. Excitation or inhibition of comb row beating provides adaptive locomotory responses, and global reversal of beat direction causes escape swimming. The diverse types of prey and feeding mechanisms of ctenophores are related to radiation in body form and morphology. The cydippid Pleurobrachia catches copepods on tentacles and undergoes unilateral ciliary reversal to sweep prey into its mouth. Mnemiopsis uses broad muscular lobes and ciliated auricles to capture and ingest prey. Beroë has giant smooth muscles and toothed macrocilia to rapidly engulf or bite through ctenophore prey, and uses reversible tissue adhesion to keep its mouth closed while swimming. Ciliary motor responses are calcium‐dependent, triggered by voltage‐activated calcium channels located along the length (reversed beating) or at the base (activation of beating) of ciliary membranes. Ciliary and muscular responses to stimuli are regulated by epithelial and mesogleal nerve nets with ultrastructurally identifiable synapses onto effector cells. Post‐embryonic patterns of comb row development in larval and adult stages are described and compared with regeneration of comb plates after surgical removal. Truly, cilia and ctenophores, like love and marriage, go together like a horse and carriage.

Two new endemic species of Ameiva (Squamata: Teiidae) from the dry forest of northwestern Peru and additional information on Ameiva concolor Ruthven, 1924.

We describe two new species of Ameiva Meyer, 1795 from the dry forest of the Northern Peruvian Andes. The new species Ameiva nodam sp. nov. and Ameiva aggerecusans sp. nov. share a divided frontal plate and are differentiated from each other and from their congeners based on genetic (12S and 16S rRNA genes) and morphological characteristics. A. nodam sp. nov. has dilated postbrachials, a maximum known snout-vent length of 101 mm, 10 longitudinal rows of ventral plates, 86-113 midbody granules, 25-35 lamellae under the fourth toe, and a color pattern with 5 longitudinal yellow stripes on the dorsum. Ameiva aggerecusans sp. nov. has not or only hardly dilated postbrachials, a maximum known snout-vent length of 99.3 mm, 10-12 longitudinal rows of ventral plates, 73-92 midbody granules, 31-39 lamellae under the fourth toe, and the females and juveniles of the species normally exhibit a cream-colored vertebral stripe on a dark dorsum ground color. We provide information on the intraspecific variation and distribution of A. concolor. Furthermore, we provide information on the environmental niches of the taxa and test for niche conservatism.

ATremadocian (EarlyOrdovician) palaeoscolecidan worm from graptolitic shales inHunanProvince,SouthChina

AbstractA new locality exposingTremadocian (EarlyOrdovician) graptolitic shales inHunanProvince,SouthChina, has yielded an exceptionally well‐preserved annulated worm. This palaeoscolecidan is described asWaflascolex changdensisgen. et sp. nov. and reveals extremely fine detail of the cuticle organization and plating array. The new taxon is characterized by three critical characters: incomplete plate rows that occur only on the posterior end of the worm (except in the posterior‐most area) and do not extend over the entire circumference or along the entire trunk; a regular rhomboidal array of platelets around intercalations; and reduced cuticular organization at the posterior termination. The unique cuticular organization and platelet ornamentation in the new taxon offer insight into functional differentiation of plates in the scleritome. Palaeoscolecid distribution through the earlyPalaeozoic is reviewed, showing that the worms were widespread in theCambrian andOrdovician, but became more restricted during theSilurian. Ordovician palaeoscolecidans are diverse in scleritome architecture, and strikingly different fromCambrian taxa, indicating that this group diversified as part of theGreatOrdovicianBiodiversificationEvent.

The burrow dwelling behavior and locomotion of palaeoscolecidian worms: New fossil evidence from the Cambrian Chengjiang fauna

Palaeoscolecidian worms are abundant components in Paleozoic shallow marine communities; however, their life habits remain poorly known. Here we present evidence of burrow dwelling behavior of palaeoscolecidian worms based on well-preserved specimens of Cricocosmia jinningensis and Mafangscolex sinensis from the lower Cambrian Maotianshan Shale. C. jinningensis was found living within elongate burrows, either of cylindrical or more rarely of swollen sac-like shape, while M. sinensis lived in elongate and slender tube-like burrows. The wall of the burrow has a sharp boundary from the surrounding sediment, which may have been consolidated by the worm itself and it resembles the recent priapulid worm Maccabeus. It is demonstrated that M. sinensis makes a snake-twisting movement in its burrow that differs from crawling behavior of C. jinningensis by the use of two rows of lateral plates. The lined burrows of Maotianshania cylindrica previously reported are in fact made by C. jinningensis and M. sinensis.